EXPLAINER | The Marcellus Shale, Explained
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The Marcellus Shale, Explained

Scott Detrow / StateImpact Pennsylvania

Marcellus Shale wells flare in Tioga County. When a test well is drilled and there are no pipelines to carry the gas, the gas is burned.

Marcellus Shale is a sedimentary rock buried thousands of feet beneath the earth’s surface.

It stretches from upstate New York south through Pennsylvania to West Virginia and west to parts of Ohio. Named after a town in upstate New York, the rock itself is millions of years old, formed from mud and organic material.

The natural gas created over millions of years as a byproduct of decomposition is trapped in tiny spaces and fissures within the rock. The Marcellus Shale is just one of many shale formations across the world.

When industry speaks of tapping shale gas, it often refers to it as a “shale play.” The Marcellus is one of the first shale plays to be tapped, after the Barnett Shale formation in Texas.

Click on the image to view StateImpact Pennsylvania’s interactive drilling app” credit=”

But how do you know who’s drilling where? StateImpact’s interactive app answers that question, by tracking every single Marcellus Shale well in Pennsylvania. The app tells you who owns each well, what violations drillers have been cited for, and allows you to read articles we’ve published about drilling near the site’s location.

The interactive map allows users to search for wells by company or location, and includes a separate map devoted to tracking what violations are happening where.

StateImpact Pennsylvania

The Shale Play app tracks drillers’ violations.

Each well has its own specific URL you can link to or share via Twitter and Facebook. If you think there’s more we need to know about the drilling site, there’s a space for you to share comments, stories or pictures.

Our app is based on data from DEP’s website. The department updates production information twice a year, and refreshes violation reports about once a month. Data covering the first six months of 2012 became available in mid-August; the next update will come in February.

Some context on the app’s information: StateImpact Pennsylvania initially only tracked wells that were actively producing gas. In June 2012, we updated the app to display every drilled well. That gives a more accurate portrayal of drilling activity.

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